var fs = require('fs')
function readFile_promise(path) {
  return new Promise((resolve, reject) => {
    fs.readFile(path, (err, data) => {
      if (err) {
        reject(new Error('Error'))
      } else {
        resolve(data.toString())
      }
    })
  })
}
async function readFile() {
  var [result1, result2] = await Promise.all([readFile_promise('../baz.txt'), readFile_promise('../foo.txt')])

  console.log('result1', result1)
  console.log('result2', result2)
}
readFile()